Hello all,
X5 3 litre diesel straight six on a 53 plate here..!
It's overheating and the expansion tank is pressurising, yet there is no sign of a free guinness when you remove the oil filler cap for inspection, so it would appear that no water is getting into the engine, just air getting into the water.
Probable cause is head gasket, and its been into the garage over the past two days, where the engine was completely flushed out with a wynns engine flush treatment, before being drained down and then hosed through with normal water, which was followed by a mixture of water, blue anti freeze, and two bottles of seel steel... or steel seel (it looks like two bottles of lime green bogey water).
It was run up, then left to cool down, but the expansion tank was once again, greatly pressurised.
If you leave it to run with the cap off, it dribbles over the top of the neck for a while, then suddenly everything shoots down inside the tank, which is followed by a few impersonations of a canadian, hot water geizer.
Having spoken with a guy at a machine shop, he states that the straight six is the worst for head gaskets, as the block and head are both alluminium, and as a result, most attempts to skim and replace / repair the head gasket will result in the threads being ripped out of the block.
In another post, i noticed that the 3 litre i engine has two thermostats, with the second being under the expansion tank, thing is, if the diesel engine has the same, i can't see it being that as it does periodically chug the water down before spouting it all back up again... although it could be stuck in the open position perhaps???
I am in desperate need of a fix on a budget here, so any and all help would be grateful... the mechanic says that the engine management was also unplugged, and having plugged it back in there's about 20 or so faults, however he says most are not worth worrying about and can probably be reset.
The mechanic i trust, as i'm a cab driver and he's the guy who keeps my work car on the road, so there's no question of him trying to pull my pants down as it were.
i've sent him a screen shot about the SNIFF TEST? which was mentioned in the previous post with the petrol engine that has a similar or identical issue, so i'll speak to him about that tomorrow.
In an absolute worst case scenario, what are my options for replacing the engine? by which i mean is there any other BMW diesel engine that would fit into the car... like the 2.5 or the 3 litre v6 or v8 perhaps... Another 3 liter straight six could end up with the same problem.........
Any and all help appreciated in advance guys